Locking member device for tow pins on a vessel

ABSTRACT

A device involving locking members (4, 5), so-called &#34;flaps&#34;, for tow pins on a vessel, e.g., a tugboat, particularly for use with tow lines, towing wire, chains, or the like, where the tow pins are positioned in pairs at the stern of the vessel, optionally capable of being raised and lowered, for guiding the tow line or similar equipment therebetween, where each tow pin in a pair is provided to the top thereof with a respective projecting locking member (4, 5), and where each tow pin (1, 2) is pivotable to permit the locking members (4, 5) to be brought by rotation into locking position by covering the opening between the upper ends of the pins, thereby limiting the vertical movement of the tow line or similar equipment positioned between the tow pins. Each locking member (4, 5) in vertical section and in a transverse direction outward from its respective tow pin (1, 2) has approximately a U-shape. The locking member (4, 5) seen in horizontal plane describes a curve in such manner that said locking members when covering the opening between the tow pins together describe a curve (6) extending in the direction of the vessel stern, and that the U-shaped cross section of the locking member at the part (11) that faces toward the vessel stern has a gently curved form, while the part (12) facing away from the vessel stem has a more upwardly oriented and less pronounced curved form.

RELATED APPLICATIONS

This application claims the priority of PCT Application No.PCT/NO96/00143, filed Jun. 12, 1996 and Norwegian Application No.952353, filed Jun. 14, 1995, which are incorporated herein by reference.

SUMMARY OF THE INVENTION

The present invention relates to a device involving locking members,so-called "flaps," for tow pins on a vessel, e.g., a tugboat,particularly for use with tow lines, towing wire, chains, or the like,where the tow pins are positioned in pairs at the stern of the vessel,capable of being raised and lowered, for guiding the tow line or similarmeans therebetween, where each tow pin in a pair is provided at the topthereof with a respective projecting locking member, and where each towpin during at least part of its vertical movement is pivotable to permitthe locking members to be brought by rotation into locking position bycovering the opening between the upper ends of the pins, therebylimiting the vertical movement of the tow line or similar meanspositioned between the tow pins.

To elucidate the prior art, reference is made to the invention describedin Norwegian Patent No. 153527.

The known locking members or "flaps" in accordance with said Norwegianpatent are primarily intended to serve as vertical stoppers and mayunder certain conditions prove less suitable in connection with towing,where the length of tow line, towing wire, chain or the like is to beadjusted, or where such towline or the like is oriented upwards.

The present invention thus aims to provide a solution for this in asimple but effective manner, and the device introduced above is thuscharacterized in that each locking member in vertical section and in atransverse direction outward from its respective tow pin hasapproximately a U-shape, that the locking member as seen in horizontalplane simultaneously describes a curve, and that the locking members attheir respective exterior, free ends terminate in a straight wall part,these straight parts engaging with one another by means of respectivemale and female means thereon when the locking members together coversaid opening between the tow pins.

In accordance with further embodiments of the device, it is consideredadvantageous that the locking member be cup-shaped, having said U crosssection along their curved length, the deepest part of the cup beingprovided with mounting holes for the placement of fixing bolts forattachment to the tow pin.

Further, it is advantageous that the part of the locking members thatfaces downward toward the opening between the adjacent tow pins, whenthe members are brought together, should have in cross section, at leastmidway along said end wall part, the form of a shallow, inverted U,where the bottom of said U is approximately flat.

In still another embodiment of the device, said locking members whencovering the opening between the tow pins will together describe a curveextending in the direction of the vessel stern, wherein the U-shapedcross section of the locking member where it faces toward the vesselstern has a gently curved form, while the part facing away from thevessel stern has a more upwardly oriented and less pronounced curvedform.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained in more detail with reference to theattached drawings.

FIG. 1 shows the device according to the invention seen in cross sectionalong the line I--I of FIG. 2.

FIG. 2 shows a simplified plan drawing of the device according to theinvention, where the locking members as drawn with solid lines are shownwhen turned toward one another, and with broken lines are shown whenrotated apart.

FIG. 3 shows the section along line III--III of FIG. 1.

FIG. 4 is a perspective view of one of the locking members according tothe invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As indicated by FIG. 1, a pair of tow pins 1, 2 is positioned preferablynear the stern of a vessel (not shown on the drawings). As is apparentfrom the section along line III--III, depicted in more detail in FIG. 3,each locking member in vertical section and in a transverse directionoutward from its respective tow pin has approximately a U-shape,indicated by reference numeral 3 on FIG. 3. As is also apparent fromFIG. 2, the respective locking members 4 and 5 (seen in horizontalplane) describe a curve. This in turn means that when locking members 4and 5 cover the opening between tow pins 1 and 2, as shown on FIGS. 1and 2, the locking members will together describe a curve 6 extending inthe direction of the vessel stern. Locking members 4 and 5 at theirrespective exterior, free ends terminate in a straight wall part 4', 5'.Wall part 4' is provided with a female means 4", and wall part 5' isprovided with a male means 5", so that said male and female means onsaid wall parts will engage with one another when the locking memberstogether cover the opening between the tow pins.

The part 7 of the locking members 4,5 that faces downward toward theopening between adjacent tow pins 1, 2, when the members are broughttogether, will have in cross section, at least midway along said endwall parts 4', 5', the form of a shallow, inverted U, with the centerpart of the U (near said wall parts 4', 5') being approximately flat.

As will be apparent from FIGS. 3 and 4, the locking member is preferablycup-shaped, having said U cross section along the curved length thereof.The deepest part 8 of said cup is provided with mounting holes 9 (seeFIG. 1) for the placement of fixing bolts 10 for attachment to therespective tow pin.

The U-shaped cross section 3 of the part of the locking member thatfaces toward the vessel stern has a gently curved form, while part 12facing away from the vessel stern has a more upwardly oriented and lesspronounced curved form.

As will be apparent from FIG. 2, locking members 4 and 5 are mounted forswinging movement outward to the side by means of tow pins 1 and 2having been made correspondingly pivotable with respect to vessel deck13. The locking members and tow pins may be raised and lowered as thetow pins simultaneously rotate during at least part of their verticalmovement, e.g., in a manner technically equivalent to that shown inconnection with Norwegian Patent No. 153527. This means, in a practicalembodiment, that when locking members 4, 5, are rotated apart (asindicated with broken lines in FIG. 2) in their lowered position, theirtop surface is approximately in alignment with the vessel deck 13, andaround the openings 14, 15 in the deck there are provided respectiveframes 16, 17, which build slightly up above the deck in height. Whentow pins 1, 2 with their locking members 4, 5 are moved upward throughthe deck 13, a simultaneous rotation of tow pins 1, 2 will occur at thefinal stage of the vertical movement, causing locking members 4, 5 torotate toward one another to cover the opening between tow pins 1, 2. Anoperation in the opposite sequence will occur when the tow pins andlocking members are moved downwards.

The purely physical configuration of the locking members shown anddescribed above is in no way considered limiting to the invention perse, as described in the patent claims, but is intended only to serve asan example with respect to a possible and, at the present time,preferred embodiment.

I claim:
 1. A locking member pair in combination with a pair of vesseltow pins particulary for use with towing means such as tow lines, towingwire, towing rope or chains, where the tow pins are positioned in pairsat the stem of the vessel, and capable of being raised and lowered, forguiding the towing means therebetween, where each tow pin during a leastpart of vertical movement is pivotable to permit the locking memberattached thereto to be rotated into locking position, the lockingmembers thereby bridging an opening between upper ends of the pins,thereby limiting the vertical movement of the towing means positionedbetween the tow pins, characterized in that each locking member invertical section and in a transverse direction outward from itsrespective tow pin has approximately a U-shape, that the locking memberas seen in a horizontal plane simultaneously describes a curve, and saidlocking members having free ends terminating in straight wall partshaving, respectively, male and female engaging means which engage whenthe locking members together bridge said opening between said tow pins.2. The locking member pair as claimed in claim 1, characterized in thatsaid locking members cup-shaped, having said U-shape cross section alongthe curved length thereof, the deepest part of the cup having mountingholes adapted to receive bolts for attachment to said tow pin.
 3. Thelocking member pair as claimed in claim 1, characterized in that a partof the locking members which face downward toward the opening betweenthe adjacent tow pins, when the members are brought together, will havea shallow, inverted U-shaped cross section, at least midway along saidend wall part, wherein the bottom of said U-shaped cross section isapproximately flat.
 4. The locking member pair as claimed in claim 1,characterized in that said locking members, when bridging said openingbetween the tow pins installed on said vessel, curve in a directiontoward the stern of said vessel, and said U-shaped cross section of saidlocking member, at the part curving in the direction toward the vesselstern has a gently curved form while the part facing in a directionopposite the stern of the vessel has a more upwardly oriented and lesspronounced curved form.
 5. The locking member pair as claimed in claim2, characterized in that said locking members, when bridging saidopening between the tow pins installed on said vessel, curve in adirection toward the stern of said vessel, and said U-shaped crosssection of said locking member, at the part curving in the directiontoward the vessel stern has a gently curved form while the part facingin a direction opposite the stern of the vessel has a more upwardlyoriented and less pronounced curved form.